Active optical cable assemblies

ABSTRACT

The present disclosure describes active optical cable assemblies. A cable assembly includes a fixed active optical connector having a transceiver, a ruggedized optical fiber cable integrated with the fixed active optical connector, a main cable assembly comprising one or more optical fiber cables, wherein the ruggedized cable is spliced to the main cable assembly; and a removable shroud configured to surround at least a portion of the fixed active optical connector plugged into a remote radio unit and to be secured to a remote radio unit. Active optical cable and remote radio unit systems and kits are also described.

RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.17/322,043, filed May 17, 2021, which claims priority from and thebenefit of U.S. Provisional Application Ser. No. 63/027,467, filed May20, 2020, the entire contents of each of which is incorporated herein byreference in their entirety.

FIELD

The present application is directed generally toward telecommunicationsequipment, and more particularly, active optical cable assemblies andremote radio systems.

BACKGROUND

Traditional optical assemblies have optical connectors on both ends ofthe assembly. These assemblies may be connected to a remote radio unit(RRU), remote radio head (RRH) or active antenna at one end and a baseband unit (BBU), another RRU, or other telecommunication equipment via asmall form-factor pluggable (SFP) optical connector (i.e., the opticalassembly is connected to one end of the SFP via an opticalconnector/adapter and the other end of the SFP (i.e., the copperconnection end) may be inserted into the RRU, RRH, etc.) to create anactive optical cable assembly. Active optical cables (AOC) represent acabling technology that accepts the same electrical inputs as atraditional copper cable, but uses optical fiber between connectors.Thus, the SFP converts an optical signal to an electrical signal. Activeoptical cables use optical-to-electrical conversion on the cable ends toimprove speed and distance performance of the cable without sacrificingcompatibility with standard electrical interfaces.

Generally speaking, mating optical connectors mechanically couple andalign the cores of optical fibers so light can pass. The better theconnector, the better the optical cleanliness of the connection (i.e.,less light is lost due to reflection or misalignment of the opticalfibers). The optical connector interface (e.g., on the optical connectorof the optical assembly and/or on the optical connector/adapter of theSFP) is very small and delicate (e.g., glass), and is susceptible todust, scratches, etc. which can affect the optical cleanliness of theconnection. Therefore, during installation, a technician must have aproper tool to inspect the ends for a clean and scratch-less opticalinterface. If the ends are dirty, the technician also must have acleaning tool and requires that the technician have special skills toperform these tasks. In addition, the technician must also test theoptical assembly for damage. Even after inspecting and cleaning theoptical interface, in many instances, it is discovered during activationof the RRU that the SFP is defective. Currently, there is not a way forthe technician to test the SFP in the field without installing it intothe RRU. Thus, there may be a need for an active optical cable assemblythat would allow for better optical cleanliness when used with, forexample, a remote radio unit.

SUMMARY

A first aspect of the present invention is directed to an end cap for anactive optical cable assembly. The end cap includes an outer protectiveshell surrounding an inner cavity, the outer protective shell having anopen end configured to receive a fixed optical connector of the activeoptical cable assembly. The inner cavity is sized to fit around thefixed optical connector and configured to form an interference fittherewith.

Another aspect of the present invention is directed to an end capadapted for use with an active optical cable assembly. The end capincludes a main body including one or more sidewalls, a closed end, andan opposing open end, the one or more sidewalls and closed end of themain body defining an inner cavity. The inner cavity is sized andconfigured to receive a fixed optical connector of the active opticalcable assembly inserted through the open end of the main body.

Another aspect of the present invention is directed to an active opticalcable assembly kit. The kit includes an active optical cable assembly,the active optical cable assembly comprising a fixed active opticalconnector and a shroud; and an end cap, the end cap including a mainbody having one or more sidewalls, a closed end, and an opposing openend, the one or more sidewalls and closed end of the main body definingan inner cavity. The inner cavity of the end cap is sized and configuredto receive the fixed optical connector of the active optical cableassembly and the main body is configured to engage the shroud of theactive optical cable assembly to secure the end cap thereto.

It is noted that aspects of the invention described with respect to oneembodiment, may be incorporated in a different embodiment although notspecifically described relative thereto. That is, all embodiments and/orfeatures of any embodiment can be combined in any way and/orcombination. Applicant reserves the right to change any originally filedclaim and/or file any new claim accordingly, including the right to beable to amend any originally filed claim to depend from and/orincorporate any feature of any other claim or claims although notoriginally claimed in that manner. These and other objects and/oraspects of the present invention are explained in detail in thespecification set forth below. Further features, advantages and detailsof the present invention will be appreciated by those of ordinary skillin the art from a reading of the figures and the detailed description ofthe preferred embodiments that follow, such description being merelyillustrative of the present invention.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a photograph of an exemplary fixed active optical connectoraccording to embodiments of the present invention.

FIG. 2 is a perspective view of an active optical cable assemblyaccording to embodiments of the present invention.

FIG. 3A is a perspective view of the active optical cable assembly ofFIG. 1A with a removable shroud according to embodiments of the presentinvention.

FIG. 3B is a photograph of an exemplary active optical cable assemblyaccording to embodiments of the present invention.

FIG. 4A is a side view of a removable shroud according to embodiments ofthe present invention.

FIG. 4B is a photograph of an exemplary removable shroud according toembodiments of the present invention.

FIG. 4C is an exploded view of the removable shroud of FIG. 4A.

FIG. 5A is a photograph of an input port to a remote radio unit andmating interface for a removable shroud according to embodiments of thepresent invention.

FIG. 5B is a photograph of the input port of FIG. 5A with the fixedactive optical connector of FIG. 1 plugged into the input port.

FIG. 6A is a photograph of an exemplary active optical cable assemblyconnected to a remote radio unit according to embodiments of the presentinvention, wherein the shroud of the assembly is omitted.

FIG. 6B is a photograph of the active optical cable assembly shown inFIG. 6A with a removable shroud according to embodiments of the presentinvention.

FIG. 7A is a perspective view of the active optical cable assembly ofFIG. 2 with an alternative removable shroud according to embodiments ofthe present invention.

FIG. 7B is a photograph of an exemplary active optical cable assemblyaccording to embodiments of the present invention.

FIG. 8A is a side view of a removable shroud according to embodiments ofthe present invention.

FIG. 8B is a photograph of an exemplary removable shroud according toembodiments of the present invention.

FIG. 9A is a photograph of an input port to a remote radio unit, with astandard SFP plugged into the input port, and a mating interface for aremovable shroud according to embodiments of the present invention.

FIG. 9B is a photograph of the input port and mating interface of FIG.9A with a standard fixed active optical connector of FIG. 1 prior tobeing plugged into the input port.

FIG. 9C is a photograph of the active optical cable assembly of FIG. 7Bwith the fixed active optical connector plugged into the input port ofthe remote radio unit.

FIG. 10A is a side view of an exemplary hybrid cable assembly accordingto embodiments of the present invention.

FIG. 10B is an enlarged partial view of the hybrid cable assembly ofFIG. 10A.

FIG. 11A is a side view of a fiber optic cable assembly according toembodiments of the present invention.

FIG. 11B is an enlarged partial view of the fiber optic cable assemblyof FIG. 11A.

FIG. 12A is a side view of an end cap for an active optical connectoraccording to embodiments of the present invention.

FIG. 12B is a perspective view of the end cap of FIG. 12A.

FIG. 12C is a side cross-sectional view of the end cap of FIGS. 12A-12B.

FIG. 13A is a photograph of an exemplary alternative removable shroud(exploded) according to embodiments of the present invention.

FIG. 13B is an enlarged photograph of the main body of the removableshroud of FIG. 13A.

FIG. 13C is a photograph of an exemplary active optical cable assemblywith the removable shroud of FIG. 13A according to embodiments of thepresent invention.

FIG. 13D is a photograph of the active optical cable assembly of FIG.13C.

FIG. 14A is a photograph of an exemplary alternative removable shroud(exploded) according to embodiments of the present invention.

FIG. 14B is a photograph of an exemplary active optical cable assemblywith the removable shroud of FIG. 14A according to embodiments of thepresent invention.

DETAILED DESCRIPTION

The present invention now is described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein; rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which illustrativeembodiments of the invention are shown. Like numbers refer to likeelements throughout and different embodiments of like elements can bedesignated using a different number of superscript indicator apostrophes(e.g., 10′, 10″, 10′″).

In the figures, certain layers, components, or features may beexaggerated for clarity, and broken lines illustrate optional featuresor operations unless specified otherwise. This invention may, however,be embodied in many different forms and should not be construed aslimited to the embodiments set forth herein; rather, these embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the invention to those skilled in theart.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, components, regions, layersand/or sections, these elements, components, regions, layers and/orsections should not be limited by these terms. These terms are only usedto distinguish one element, component, region, layer or section fromanother region, layer or section. Thus, a first element, component,region, layer or section discussed below could be termed a secondelement, component, region, layer or section without departing from theteachings of the present invention. The sequence of operations (orsteps) is not limited to the order presented in the claims or figuresunless specifically indicated otherwise.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the specification andrelevant art and should not be interpreted in an idealized or overlyformal sense unless expressly so defined herein. Well-known functions orconstructions may not be described in detail for brevity and/or clarity.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising”, when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

As used herein, phrases such as “between X and Y” and “between about Xand Y” should be interpreted to include X and Y. As used herein, phrasessuch as “between about X and Y” mean “between about X and about Y.” Asused herein, phrases such as “from about X to Y” mean “from about X toabout Y.”

Pursuant to embodiments of the present invention, active optical cableassemblies are provided that may enhance the optical cleanliness of anoptical connection. Active optical cable and remote radio unit systemsare also provided herein. Embodiments of the present invention will nowbe discussed in greater detail with reference to FIGS. 1-14B.

Referring now to the drawings, an active optical cable assembly 10according to embodiments of the present is shown in FIGS. 1-2 . As canbe seen in FIGS. 1-2 , the cable assembly 10 may include a fiber opticcable 14. In some embodiments, the fiber optic cable 14 may be aruggedized fiber optic cable. At one end of the ruggedized fiber opticcable 14, a fixed active optical connector (with transceiver) 12 (e.g.,an active optical connector) may be integrated with the cable 14. Thefixed optical connector 12 is configured to be inserted into (i.e.,plugged into) and received by an input port 32 of a remote radio unit 30(see, e.g., FIGS. 5A-5B, FIGS. 6A-6B, and FIGS. 9A-9C). For example, insome embodiments, the fixed optical connector 12 may be a smallform-factor pluggable (SFP) optical connector. As discussed above, theSFP converts an optical signal to an electrical signal. Integrating anSFP optical connector 12 into the optical assembly 10 of the presentinvention eliminates the optical connector interface issue describedabove. Thus, no special tools are required to test or clean the opticalconnectors, thereby helping to reduce installation time and costsassociated therewith. In addition, because the non-integrated end of theSFP optical connector 12 is an electrical contact, the optical assembly10 is easier to handle by a technician (i.e., not as delicate as anoptical connector interface). Moreover, by eliminating the connector(optical assembly) to connector (SFP) optical connection, insertion loss(IL) and return loss (RL) may be improved, thereby increasing opticalcleanliness. Furthermore, the active optical cable assembly 10 of thepresent invention (i.e., having an integrated SFP optical connector 12)can be tested prior to installation, thereby eliminating a techniciandiscovering that an SFP is defective during RRU activation.

In some embodiments, the fixed optical connector 12 may have a pull tab17 attached thereto. The pull tab 17 may be used by a technician to gripwhen removing (i.e., pulling) the fixed optical connector 12 from theinput port 32 of the remote radio unit 30. In some embodiments, the pulltab 17 may also be used to help secure or lock the fixed connector 12 inplace within the remote radio unit 30 (see, e.g., FIGS. 13A-13D).

The active optical cable assembly 10 of the present invention mayfurther include a main cable assembly 11. In some embodiments, the maincable assembly 11 may comprise one or more fiber optic cables 16 withactive optical connectors 18 (i.e., an optical cable assembly) (seealso, e.g., FIGS. 11A-11B). In some embodiments, each fiber optic cable14, 16 (i.e., the ruggedized fiber optic cable 14 and the one or morefiber optic cables 16 of the cable assembly 11) includes at least oneoptical fiber (not shown) that may be spliced together at a splicetransition area (i.e., within a protective enclosure 15) (see, e.g.,FIGS. 2, 3A-3B, 7A-7B, 10A-10B, and 11A-11B). In some embodiments, theoptical fibers may be fusion spliced together. In some embodiments, theoptical fibers may comprise ribbonized optical fibers 62 (see, e.g.,FIGS. 11A-11B).

As shown in FIGS. 3A-3B, in some embodiments, the active optical cableassembly 10 may further include a removable shroud 20. The shroud 20 isconfigured to surround at least a portion of the fixed optical connector12. For example, the shroud 20 may surround a portion of the fixedoptical connector 12 that extends outwardly from the remote radio unit30 when the fixed connector 12 is plugged into the remote radio unit 30(see, e.g., FIG. 6B).

The removable shroud 20 is further shown in FIGS. 4A-4C. As illustratedin FIGS. 4A-4C, the shroud 20 includes a tubular main body 22. At oneend, the main body 22 comprises a locking section 26 with a mating end26 a. A threaded section 27 resides at the opposing end of the main body22. The removable shroud 20 further includes a locking mechanism 24 thatis slidable along the main body 22. A biasing member 23 (e.g., a spring)is coupled to the main body 22 of the shroud 20 and resides between thelocking section 26 and the locking mechanism 24. As described in furtherdetail below, the locking mechanism 24, locking section 26, and biasingmember 23 may function together as a “push-pull” latching mechanism tosecure the shroud 20 to a remote radio unit 30. In some embodiments, theshroud 20 also includes a coupling nut 28 and coupling gasket 28 a. Thecoupling nut 28 is configured to be screwed onto the threaded section 27of the main body 22. In some embodiments, the shroud 20 may furthercomprise a sealed end cap 25.

The locking section 26 (and mating end 26 a) of the removable shroud 20may be configured to secure the shroud 20 to the remote radio unit 30(i.e., after a fixed active optical connector 12 has been plugged intoan input port 32). In some embodiments, the shroud 20 may be configuredto be secured to a mating interface 34 corresponding to an input port 32of the remote radio unit 30 (see, e.g., FIG. 6B). For example, in someembodiments, the shroud 20 may form a bayonet connection with the matinginterface 34. As shown in FIGS. 5A-5B, the mating interface 34 maycomprise an annular flange 35. In some embodiments, a pair of arms 36may extend outwardly from the annular flange 35. Each arm may comprise asecuring feature 38, such as, a snap-fit feature or the like. In someembodiments, to secure the shroud 20 to the remote radio unit 30, themating end 26 a is aligned with the mating interface 34 such that thelocking section 26 is located inside the annular flange 35 and betweenthe outwardly extending arms 36. Next, the locking mechanism 24 ispushed (or slid) along the main body 22 toward the locking section 26(compressing the biasing member 23) until the locking mechanism 24engages the securing feature 38 of the arms 36 (i.e., the arms 36 arebetween the locking section 26 and the locking mechanism 24). Thelocking mechanism 24 is then rotated to lock the securing feature 38within the locking mechanism 24, thereby securing the shroud 20 to theremote radio unit 30. Once the shroud 20 is secured to the remote radiounit 30, the coupling nut 28 may be screwed onto the threaded section 27of the main body 22. As the coupling nut 28 is tightened, the couplinggasket 28 a is squeezed against the ruggedized cable 14, therebycreating a seal between the removable shroud 20 and the cable 14.

To remove the shroud 20 from the remote radio unit 30, the coupling nut28 is unscrewed from the threaded section 27 and the locking mechanism24 is rotated in an opposite direction to release the securing feature38 from the locking mechanism 24. Once released, the biasing member 23pushes the locking mechanism 24 away from the locking section 26,thereby allowing the shroud 20 to be pulled away from the matinginterface 34 of the remote radio unit 30.

In some embodiments, the mating end 26 a of the shroud 20 may beconfigured to form an interference fit (e.g., via gasket compression)with the mating interface 34 of the remote radio unit 30. In otherembodiments, the shroud 20 may comprise threads that correspond tothreads on the mating interface 34, allowing the shroud 20 to be secured(i.e., screwed) onto the remote radio unit 30. The shroud 20 may help toenhance or increase optical cleanliness by providing protection to theoptical connection between the fixed optical connector 12 and the remoteradio unit 30 (e.g., protecting from dust and/or environmentalconditions). In addition, in some embodiments, the shroud 20 maycomprise one or more features configured to protect the fixed opticalconnector 12 from vibration and/or mechanical shock. For example, insome embodiments, the shroud 20 may be molded such that the interior ofthe shroud 20 corresponds to the shape of the fixed connector 12 whichhelps to hold the fixed connector 12 in place. In some embodiments, thevibration reduction and/or alignment feature may be a gasket or slottedspring feature. In some embodiments, the removable shroud 20 may beformed from a polymeric material, such as polyurethane, rubber,acrylonitrile butadiene styrene (ABS), or the like.

Referring to FIGS. 7A-7B and FIGS. 8A-8B, according to embodiments ofthe present invention, an alternative removable shroud 200 that may beused with the active optical cable assembly 10 is illustrated. As shownin FIGS. 7A-8B and FIGS. 8A-8B, in some embodiments, at least a portionof the shroud 200 may be formed from a metallic material. The metallicportion 202 of the shroud 200 may be configured to surround at least aportion of the fixed optical connector 12 and be secured to the remoteradio unit 30 (e.g., by mating end 202 a). In some embodiments, theshroud 200 may further comprise a polymeric strain relief section 204.The polymer strain relief section 204 may be configured to bend with thefiber optic cable 14, thereby relieving strain from the removable shroud200 and fixed optical connector 12 within the shroud 200. The strainrelief section 204 of the shroud 200 may further comprise a coupling nut206 configured to threaded with the metallic portion 202. Similar to theshroud 20 described above, as the coupling nut 206 is threaded with themetallic portion 202, a coupling mechanism 203 squeezes a couplinggasket 203 a against the ruggedized cable 14, thereby creating a sealbetween the shroud 200 and the cable 14.

FIGS. 9A-9C illustrate a remote radio unit 30 having a different matinginterface 34′. As shown in FIGS. 9A-9B, instead of a pair of arms 36with a securing feature 38, in some embodiments, the mating interface34′ may have an extended annular flange 35′. The extended annular flange35′ may comprise one or more slots 38′, each having an open end 38 a′.In some embodiments, to secure the shroud 200 to a remote radio unit 30having mating interface 34′, the mating end 202 a of the metallicportion 202 is aligned with the extended annular flange 35′ such thatcorresponding securing features (not shown) within the mating end 202 aalign with each open end 38 a′ of the slots 38′. The metallic portion202 is rotated to lock each securing feature within a respective slot38′, thereby securing the removable shroud 200 to the remote radio unit30.

To remove the shroud 200 from the remote radio unit 30, the coupling nut206 is unscrewed from the metallic portion 202 and the metallic portion202 is rotated in an opposite direction to release the securing featuresfrom the slots 38′. Once released, the shroud 200 may be pulled awayfrom the mating interface 34′ of the remote radio unit 30.

Similar to the removable shroud 20 described above, the removable shroud200 may help to enhance or increase optical cleanliness by helping toprotect the optical connection between the fixed optical connector 12and the remote radio unit 30. In some embodiments, the shroud 200 may beconfigured to form an interference fit with the mating interface 34 ofthe remote radio unit 30. In other embodiments, the shroud 200 maycomprise threads that correspond to threads on the mating interface 34,thereby allowing the shroud 200 to be secured (i.e., screwed) onto theremote radio unit 30. In addition, in some embodiments, the shroud 200may comprise one or more features configured to protect the fixedoptical connector 12 from vibration and/or mechanical shock. Theremovable shrouds 20, 200 also provide protection against environmentalconditions such as rain, snow, etc.

Referring now to FIGS. 10A-10B and FIGS. 11A-11B, in some embodiments,the main cable assembly 11 may be a hybrid cable assembly 40 (FIGS.10A-10B) or fiber optic cable assembly 50 (FIGS. 11A-11B). As shown inFIGS. 10A-10B, the hybrid cable assembly 40 includes a hybrid cable 44that may comprise optical cables (i.e., optical fibers) 16 with opticalconnectors 18 and power conductors (e.g., copper conductors) 42. Thehybrid cable assembly 40 may include one or more transition or breakoutsections (i.e., protective enclosures) 45 allowing the hybrid cableassembly 40 to breakout into two or more active optical cable assemblies10. For example, as shown in FIGS. 10A-10B, the hybrid cable assembly 40may be broken out into two active optical cable assemblies 10 with acentral power cable 46. As discussed herein, in some embodiments, thefiber optic cables 14, 16 include at least one optical fiber (not shown)that may be spliced together at a splice transition area (i.e., withinthe protective enclosures 15, 45). In some embodiments, the opticalfibers may be fusion spliced together.

As shown in FIGS. 11A-11B, the fiber optic cable assembly 50 includes afiber optic cable 54 that may comprise ribbonized optical fibers 62. Thefiber optic cable assembly 50 may include a transition or breakoutsection 55 allowing the fiber optic cable assembly 50 to breakout intotwo or more active optical cable assemblies 10 (with respective fixedoptical connectors 12). The fiber optic cable assembly 50 may includeany number of active optical cable assemblies 10. For example, as shownin FIG. 11A, the fiber optic cable assembly 50 may include six activeoptical cable assemblies 10 with fixed optical connectors 12 (i.e., 12-1through 12-6). As shown in FIG. 11B, in some embodiments, the opticalfibers 62 may be spliced together at a splice transition area 64. Insome embodiments, the optical fibers 62 may be fusion spliced together.In some embodiments, the splice transition area 64 (e.g., fusionspliced) may be encapsulated by a protective enclosure 60, such as anarmored furcation tube. The protective enclosure 60 may be secured tothe fiber optic cable 54 via an adhesive heat-shrink tube or over-moldedpolymer 66.

Referring now to FIGS. 12A-12C, an end cap 70 for the active opticalcable assembly 10 of the present invention is illustrated. The end cap70 is configured to fit around the fixed active optical connector 12 andprotect the connector 12 (and transceiver) during, for example, shipmentand/or storage (e.g., from dust and/or environmental conditions) beforethe connector 12 is plugged into a remote radio unit 30. The end cap 70comprises an outer protective shell 72 surrounding an inner cavity 74with an open end. The open end is configured to allowed the end cap 70be slid onto the fixed optical connector 12. In some embodiments, theinner cavity 74 is configured to form an interference fit with the fixedoptical connector 12. For example, as shown in FIGS. 12B-12C, aninterior gasket 73 may be molded such that the inner cavity 74corresponds with the shape of the fixed connector 12 (e.g., rectangularin shape), allowing the end cap 70 to form an interference fit with theactive optical connector 12, and thereby helping to reduce vibrationand/or mechanical shock on the optical connector 12.

As shown in FIGS. 12A-12C, in some embodiments, the end cap 70 may haveone or more additional securing features 76. The securing features 76may extend outwardly in an axial direction from the open end of the endcap 70. The securing features 76 may be configured to secure the end cap70 to the removable shroud 20, 200 described herein. Any number of knownsecuring features 76 may be used with the end cap 70. For example, insome embodiments, the securing feature 76 may be a snap-fit feature thatcan be deflected radially inward until a protrusion 76 a, for example,engages with a corresponding feature of the removable shroud 20, 200.

In some embodiments, the end cap 70 may further comprise an annulargasket 75 adjacent to the open end. The annular gasket 75 may help toprovide a water-tight seal, for example, between the end cap 70 and theremovable shroud 20, 200. In some embodiments, the end cap 70 mayfurther include an aperture 77. The aperture 77 may be used duringstorage and/or may be used to help remove the end cap 70 from a fixedoptical connector 12.

Referring now to FIGS. 13A-13D, an alternative removable shroud 300according to embodiments of the present invention is illustrated. Asshown in FIGS. 13A-13C, in some embodiments, the shroud 300 has a mainbody 302. The main body 302 has an inner cavity 304 configured to fit atleast a portion of an active optical connector 12, 12′ (see, e.g., FIG.13B). In some embodiments, the inner cavity 304 is configured to form aninterference fit with at least a portion of an active optical connector12, 12′. The shroud 300 further has a latching mechanism 306 that ispivotably coupled to the main body 302. At one end of the latchingmechanism 306 is a latch (or hook) 306 a configured to secure the shroud300 to a remote radio unit 30. At the other end of the latchingmechanism is a pull tab 317. To secure the shroud 300 to a remote radiounit 30, the main body 302 is slid over the active optical connector 12,12′ (i.e., already plugged into the input port 32, 32′ of the remoteradio unit 30) and the pull tab 317 is pushed toward the main body 302which pivots the latch 306 to lock with a corresponding securing feature(not shown) on the remote radio unit 30, thereby securing the shroud 300to the remote radio unit 30.

The shroud 300 further includes a coupling nut 308 configured to bethreaded with a threaded section 302 a of the main body 302. Similar tothe shrouds 20, 200 described herein, as the coupling nut 308 isthreaded with the threaded section 302 a, a coupling mechanism 303squeezes a coupling gasket 305 against the ruggedized cable 14, therebycreating a seal between the shroud 300 and the cable 14. FIG. 13D showsthe removable shroud 300 in combination with an active optical cableassembly 10 of the present invention.

Referring now to FIGS. 14A-14B, an alternative removable shroud 400according to embodiments of the present invention is illustrated.Removable shroud 400 is similar to removable shroud 20 described herein.Thus, properties and/or features of the shroud 400 may be describedabove in references to FIGS. 4A-4C and duplicate discussion thereof maybe omitted herein for the purposes of discussing FIGS. 14A-14B.

As shown in FIG. 14A, the shroud 400 includes a tubular main body 402.At one end, the main body 402 comprises a locking section 406 with amating end 406 a. A threaded section 402 a resides at the opposing endof the main body 402. The shroud 400 further includes a lockingmechanism 404 that is slidable along the main body 402. A biasing member(not shown) is coupled to the main body 402 and resides between thelocking section 406 and the locking mechanism 404. Similar to shroud 20described herein, the locking mechanism 404, locking section 406, andbiasing member may function together as a “push-pull” latching mechanismto secure the removable shroud 400 to a remote radio unit 30. In someembodiments, the shroud 400 also includes a coupling nut 408, couplingmechanism 407, and coupling gasket 405. The coupling nut 408 isconfigured to be screwed onto the threaded section 402 a of the mainbody 402. Similar to the shrouds 20, 200, 300 described herein, as thecoupling nut 408 is threaded with the threaded section 402 a, thecoupling mechanism 407 squeezes the coupling gasket 405 against theruggedized cable 14, thereby creating a seal between the shroud 400 andthe cable 14. FIG. 14B shows the removable shroud 400 in combinationwith an active optical cable assembly 10 of the present invention.

The foregoing is illustrative of the present invention and is not to beconstrued as limiting thereof. Although exemplary embodiments of thisinvention have been described, those skilled in the art will readilyappreciate that many modifications are possible in the exemplaryembodiments without materially departing from the novel teachings andadvantages of this invention. Accordingly, all such modifications areintended to be included within the scope of this invention as defined inthe claims. The invention is defined by the following claims, withequivalents of the claims to be included therein.

That which is claimed is:
 1. An end cap for an active optical cableassembly, the end cap comprising: an outer protective shell surroundingan inner cavity, the outer protective shell having an open endconfigured to receive a fixed optical connector of the active opticalcable assembly, wherein the inner cavity is sized to fit around thefixed optical connector and configured to form an interference fittherewith.
 2. The end cap according to claim 1, further comprising aninterior gasket molded within the inner cavity which correspond with anouter profile of the fixed optical connector.
 3. The end cap accordingto claim 2, wherein the interior gasket has a rectangular shape.
 4. Theend cap according to claim 1, further comprising one or more securingfeatures configured to engage the active optical cable assembly.
 5. Theend cap according to claim 4, wherein the one or more securing featuresextend outwardly in an axial direction from the open end of the end cap6. The end cap according to claim 4, wherein the one or more securingfeatures are configured to engage a shroud of the active optical cableassembly.
 7. The end cap according to claim 4, wherein the one or moresecuring features comprise a snap-fit feature configured to deflectradially inwardly or outwardly until a protrusion engages with acorresponding feature of the active optical cable assembly.
 8. The endcap according to claim 1, further comprising an annular gasket adjacentto the open end.
 9. The end cap according to claim 1, wherein the fixedoptical connector is a small form-factor pluggable (SFP) opticalconnector.
 10. The end cap according to claim 1, in combination with anactive optical cable assembly comprising a shroud, wherein the end capis engaged with the shroud of the active optical cable assembly tosecure the end cap to the active optical cable assembly.
 11. An end capadapted for use with an active optical cable assembly, the end capcomprising: a main body including one or more sidewalls, a closed end,and an opposing open end, the one or more sidewalls and closed end ofthe main body defining an inner cavity, wherein the inner cavity issized and configured to receive a fixed optical connector of the activeoptical cable assembly inserted through the open end of the main body.12. The end cap according to claim 11, wherein the inner cavitycorresponds with an outer profile of the fixed optical connector. 13.The end cap according to claim 11, further comprising one or moresecuring features configured to engage the active optical cableassembly.
 14. The end cap according to claim 13, wherein the one or moresecuring features are configured to engage a shroud of the activeoptical cable assembly.
 15. The end cap according to claim 11, whereinthe fixed optical connector is a small form-factor pluggable (SFP)transceiver.
 16. The end cap according to claim 11, wherein the mainbody is formed from a polymeric material.
 17. The end cap according toclaim 11, in combination with an active optical cable assemblycomprising a shroud, wherein the end cap is engaged with the shroud ofthe active optical cable assembly to secure the end cap to the activeoptical cable assembly.
 18. An active optical cable assembly kit, thekit comprising: an active optical cable assembly, the active opticalcable assembly comprising a fixed active optical connector and a shroud;and an end cap, the end cap comprising a main body having one or moresidewalls, a closed end, and an opposing open end, the one or moresidewalls and closed end of the main body defining an inner cavity,wherein the inner cavity of the end cap is sized and configured toreceive the fixed optical connector of the active optical cable assemblyand the main body is configured to engage the shroud of the activeoptical cable assembly to secure the end cap thereto.
 19. The activeoptical cable assembly kit according to claim 18, wherein the fixedoptical connector is a small form-factor pluggable (SFP) opticalconnector.
 20. The active optical cable assembly kit according to claim18, wherein the end cap further comprising one or more securing featuresconfigured to engage with the shroud of the active optical cableassembly to secure the end cap thereto.